<feed xmlns='http://www.w3.org/2005/Atom'>
<title>wireguard-linux/fs/btrfs/inode-map.c, branch jd/unified-crypt-queue</title>
<subtitle>WireGuard for the Linux kernel</subtitle>
<id>https://git.zx2c4.com/wireguard-linux/atom/fs/btrfs/inode-map.c?h=jd%2Funified-crypt-queue</id>
<link rel='self' href='https://git.zx2c4.com/wireguard-linux/atom/fs/btrfs/inode-map.c?h=jd%2Funified-crypt-queue'/>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/'/>
<updated>2020-03-23T16:01:55Z</updated>
<entry>
<title>btrfs: Remove __ prefix from btrfs_block_rsv_release</title>
<updated>2020-03-23T16:01:55Z</updated>
<author>
<name>Nikolay Borisov</name>
<email>nborisov@suse.com</email>
</author>
<published>2020-03-10T08:59:31Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=63f018be577f7cb4787f594400976b4e779b5cfb'/>
<id>urn:sha1:63f018be577f7cb4787f594400976b4e779b5cfb</id>
<content type='text'>
Currently the non-prefixed version is a simple wrapper used to hide
the 4th argument of the prefixed version. This doesn't bring much value
in practice and only makes the code harder to follow by adding another
level of indirection. Rectify this by removing the __ prefix and
have only one public function to release bytes from a block reservation.
No semantic changes.

Signed-off-by: Nikolay Borisov &lt;nborisov@suse.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: keep track of which extents have been discarded</title>
<updated>2020-01-20T15:40:57Z</updated>
<author>
<name>Dennis Zhou</name>
<email>dennis@kernel.org</email>
</author>
<published>2019-12-14T00:22:12Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=a7ccb255852413dd59263e551fd0ef13f76fc9b9'/>
<id>urn:sha1:a7ccb255852413dd59263e551fd0ef13f76fc9b9</id>
<content type='text'>
Async discard will use the free space cache as backing knowledge for
which extents to discard. This patch plumbs knowledge about which
extents need to be discarded into the free space cache from
unpin_extent_range().

An untrimmed extent can merge with everything as this is a new region.
Absorbing trimmed extents is a tradeoff to for greater coalescing which
makes life better for find_free_extent(). Additionally, it seems the
size of a trim isn't as problematic as the trim io itself.

When reading in the free space cache from disk, if sync is set, mark all
extents as trimmed. The current code ensures at transaction commit that
all free space is trimmed when sync is set, so this reflects that.

Signed-off-by: Dennis Zhou &lt;dennis@kernel.org&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: qgroup: Always free PREALLOC META reserve in btrfs_delalloc_release_extents()</title>
<updated>2019-10-15T16:50:07Z</updated>
<author>
<name>Qu Wenruo</name>
<email>wqu@suse.com</email>
</author>
<published>2019-10-14T06:34:51Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=8702ba9396bf7bbae2ab93c94acd4bd37cfa4f09'/>
<id>urn:sha1:8702ba9396bf7bbae2ab93c94acd4bd37cfa4f09</id>
<content type='text'>
[Background]
Btrfs qgroup uses two types of reserved space for METADATA space,
PERTRANS and PREALLOC.

PERTRANS is metadata space reserved for each transaction started by
btrfs_start_transaction().
While PREALLOC is for delalloc, where we reserve space before joining a
transaction, and finally it will be converted to PERTRANS after the
writeback is done.

[Inconsistency]
However there is inconsistency in how we handle PREALLOC metadata space.

The most obvious one is:
In btrfs_buffered_write():
	btrfs_delalloc_release_extents(BTRFS_I(inode), reserve_bytes, true);

We always free qgroup PREALLOC meta space.

While in btrfs_truncate_block():
	btrfs_delalloc_release_extents(BTRFS_I(inode), blocksize, (ret != 0));

We only free qgroup PREALLOC meta space when something went wrong.

[The Correct Behavior]
The correct behavior should be the one in btrfs_buffered_write(), we
should always free PREALLOC metadata space.

The reason is, the btrfs_delalloc_* mechanism works by:
- Reserve metadata first, even it's not necessary
  In btrfs_delalloc_reserve_metadata()

- Free the unused metadata space
  Normally in:
  btrfs_delalloc_release_extents()
  |- btrfs_inode_rsv_release()
     Here we do calculation on whether we should release or not.

E.g. for 64K buffered write, the metadata rsv works like:

/* The first page */
reserve_meta:	num_bytes=calc_inode_reservations()
free_meta:	num_bytes=0
total:		num_bytes=calc_inode_reservations()
/* The first page caused one outstanding extent, thus needs metadata
   rsv */

/* The 2nd page */
reserve_meta:	num_bytes=calc_inode_reservations()
free_meta:	num_bytes=calc_inode_reservations()
total:		not changed
/* The 2nd page doesn't cause new outstanding extent, needs no new meta
   rsv, so we free what we have reserved */

/* The 3rd~16th pages */
reserve_meta:	num_bytes=calc_inode_reservations()
free_meta:	num_bytes=calc_inode_reservations()
total:		not changed (still space for one outstanding extent)

This means, if btrfs_delalloc_release_extents() determines to free some
space, then those space should be freed NOW.
So for qgroup, we should call btrfs_qgroup_free_meta_prealloc() other
than btrfs_qgroup_convert_reserved_meta().

The good news is:
- The callers are not that hot
  The hottest caller is in btrfs_buffered_write(), which is already
  fixed by commit 336a8bb8e36a ("btrfs: Fix wrong
  btrfs_delalloc_release_extents parameter"). Thus it's not that
  easy to cause false EDQUOT.

- The trans commit in advance for qgroup would hide the bug
  Since commit f5fef4593653 ("btrfs: qgroup: Make qgroup async transaction
  commit more aggressive"), when btrfs qgroup metadata free space is slow,
  it will try to commit transaction and free the wrongly converted
  PERTRANS space, so it's not that easy to hit such bug.

[FIX]
So to fix the problem, remove the @qgroup_free parameter for
btrfs_delalloc_release_extents(), and always pass true to
btrfs_inode_rsv_release().

Reported-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Fixes: 43b18595d660 ("btrfs: qgroup: Use separate meta reservation type for delalloc")
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Signed-off-by: Qu Wenruo &lt;wqu@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: rename the btrfs_calc_*_metadata_size helpers</title>
<updated>2019-09-09T12:59:13Z</updated>
<author>
<name>Josef Bacik</name>
<email>josef@toxicpanda.com</email>
</author>
<published>2019-08-22T19:14:33Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=2bd36e7b4fd60d4ff5f9ba6a0ad84557ae4803c4'/>
<id>urn:sha1:2bd36e7b4fd60d4ff5f9ba6a0ad84557ae4803c4</id>
<content type='text'>
btrfs_calc_trunc_metadata_size differs from trans_metadata_size in that
it doesn't take into account any splitting at the levels, because
truncate will never split nodes.  However truncate _and_ changing will
never split nodes, so rename btrfs_calc_trunc_metadata_size to
btrfs_calc_metadata_size.  Also btrfs_calc_trans_metadata_size is purely
for inserting items, so rename this to btrfs_calc_insert_metadata_size.
Making these clearer will help when I start using them differently in
upcoming patches.

Reviewed-by: Nikolay Borisov &lt;nborisov@suse.com&gt;
Signed-off-by: Josef Bacik &lt;josef@toxicpanda.com&gt;
Reviewed-by: David Sterba &lt;dsterba@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>Btrfs: wake up inode cache waiters sooner to reduce waiting time</title>
<updated>2019-09-09T12:59:02Z</updated>
<author>
<name>Filipe Manana</name>
<email>fdmanana@suse.com</email>
</author>
<published>2019-07-04T15:25:00Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=32e534402ad52e9f35c32be68e25213db722892b'/>
<id>urn:sha1:32e534402ad52e9f35c32be68e25213db722892b</id>
<content type='text'>
If we need to start an inode caching thread, because none currently exists
on disk, we can wake up all waiters as soon as we mark the range starting
at root's highest objectid + 1 and ending at BTRFS_LAST_FREE_OBJECTID as
free, so that they don't need to wait for the caching thread to start and
do some progress. We follow the same approach within the caching thread,
since as soon as it finds a free range and marks it as free space in the
cache, it wakes up all waiters. So improve this by adding such a wakeup
call after marking that initial range as free space.

Fixes: a47d6b70e28040 ("Btrfs: setup free ino caching in a more asynchronous way")
Reviewed-by: Nikolay Borisov &lt;nborisov@suse.com&gt;
Signed-off-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>Btrfs: fix inode cache waiters hanging on path allocation failure</title>
<updated>2019-09-09T12:59:02Z</updated>
<author>
<name>Filipe Manana</name>
<email>fdmanana@suse.com</email>
</author>
<published>2019-07-04T15:24:44Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=9d123a35d7e97bb2139747b16127c9b22b6a593e'/>
<id>urn:sha1:9d123a35d7e97bb2139747b16127c9b22b6a593e</id>
<content type='text'>
If the caching thread fails to allocate a path, it returns without waking
up any cache waiters, leaving them hang forever. Fix this by following the
same approach as when we fail to start the caching thread: print an error
message, disable inode caching and make the wakers fallback to non-caching
mode behaviour (calling btrfs_find_free_objectid()).

Fixes: 581bb050941b4f ("Btrfs: Cache free inode numbers in memory")
Reviewed-by: Nikolay Borisov &lt;nborisov@suse.com&gt;
Signed-off-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>Btrfs: fix inode cache waiters hanging on failure to start caching thread</title>
<updated>2019-09-09T12:59:01Z</updated>
<author>
<name>Filipe Manana</name>
<email>fdmanana@suse.com</email>
</author>
<published>2019-07-04T15:24:32Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=a68ebe0790fc88b4314d17984a2cf99ce2361901'/>
<id>urn:sha1:a68ebe0790fc88b4314d17984a2cf99ce2361901</id>
<content type='text'>
If we fail to start the inode caching thread, we print an error message
and disable the inode cache, however we never wake up any waiters, so they
hang forever waiting for the caching to finish. Fix this by waking them
up and have them fallback to a call to btrfs_find_free_objectid().

Fixes: e60efa84252c05 ("Btrfs: avoid triggering bug_on() when we fail to start inode caching task")
Reviewed-by: Nikolay Borisov &lt;nborisov@suse.com&gt;
Signed-off-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>Btrfs: fix inode cache block reserve leak on failure to allocate data space</title>
<updated>2019-09-09T12:59:01Z</updated>
<author>
<name>Filipe Manana</name>
<email>fdmanana@suse.com</email>
</author>
<published>2019-07-04T15:24:19Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=29d47d00e0ae61668ee0c5d90bef2893c8abbafa'/>
<id>urn:sha1:29d47d00e0ae61668ee0c5d90bef2893c8abbafa</id>
<content type='text'>
If we failed to allocate the data extent(s) for the inode space cache, we
were bailing out without releasing the previously reserved metadata. This
was triggering the following warnings when unmounting a filesystem:

  $ cat -n fs/btrfs/inode.c
  (...)
  9268  void btrfs_destroy_inode(struct inode *inode)
  9269  {
  (...)
  9276          WARN_ON(BTRFS_I(inode)-&gt;block_rsv.reserved);
  9277          WARN_ON(BTRFS_I(inode)-&gt;block_rsv.size);
  (...)
  9281          WARN_ON(BTRFS_I(inode)-&gt;csum_bytes);
  9282          WARN_ON(BTRFS_I(inode)-&gt;defrag_bytes);
  (...)

Several fstests test cases triggered this often, such as generic/083,
generic/102, generic/172, generic/269 and generic/300 at least, producing
stack traces like the following in dmesg/syslog:

  [82039.079546] WARNING: CPU: 2 PID: 13167 at fs/btrfs/inode.c:9276 btrfs_destroy_inode+0x203/0x270 [btrfs]
  (...)
  [82039.081543] CPU: 2 PID: 13167 Comm: umount Tainted: G        W         5.2.0-rc4-btrfs-next-50 #1
  [82039.081912] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
  [82039.082673] RIP: 0010:btrfs_destroy_inode+0x203/0x270 [btrfs]
  (...)
  [82039.083913] RSP: 0018:ffffac0b426a7d30 EFLAGS: 00010206
  [82039.084320] RAX: ffff8ddf77691158 RBX: ffff8dde29b34660 RCX: 0000000000000002
  [82039.084736] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8dde29b34660
  [82039.085156] RBP: ffff8ddf5fbec000 R08: 0000000000000000 R09: 0000000000000000
  [82039.085578] R10: ffffac0b426a7c90 R11: ffffffffb9aad768 R12: ffffac0b426a7db0
  [82039.086000] R13: ffff8ddf5fbec0a0 R14: dead000000000100 R15: 0000000000000000
  [82039.086416] FS:  00007f8db96d12c0(0000) GS:ffff8de036b00000(0000) knlGS:0000000000000000
  [82039.086837] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [82039.087253] CR2: 0000000001416108 CR3: 00000002315cc001 CR4: 00000000003606e0
  [82039.087672] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [82039.088089] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [82039.088504] Call Trace:
  [82039.088918]  destroy_inode+0x3b/0x70
  [82039.089340]  btrfs_free_fs_root+0x16/0xa0 [btrfs]
  [82039.089768]  btrfs_free_fs_roots+0xd8/0x160 [btrfs]
  [82039.090183]  ? wait_for_completion+0x65/0x1a0
  [82039.090607]  close_ctree+0x172/0x370 [btrfs]
  [82039.091021]  generic_shutdown_super+0x6c/0x110
  [82039.091427]  kill_anon_super+0xe/0x30
  [82039.091832]  btrfs_kill_super+0x12/0xa0 [btrfs]
  [82039.092233]  deactivate_locked_super+0x3a/0x70
  [82039.092636]  cleanup_mnt+0x3b/0x80
  [82039.093039]  task_work_run+0x93/0xc0
  [82039.093457]  exit_to_usermode_loop+0xfa/0x100
  [82039.093856]  do_syscall_64+0x162/0x1d0
  [82039.094244]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [82039.094634] RIP: 0033:0x7f8db8fbab37
  (...)
  [82039.095876] RSP: 002b:00007ffdce35b468 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
  [82039.096290] RAX: 0000000000000000 RBX: 0000560d20b00060 RCX: 00007f8db8fbab37
  [82039.096700] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000560d20b00240
  [82039.097110] RBP: 0000560d20b00240 R08: 0000560d20b00270 R09: 0000000000000015
  [82039.097522] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f8db94bce64
  [82039.097937] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffdce35b6f0
  [82039.098350] irq event stamp: 0
  [82039.098750] hardirqs last  enabled at (0): [&lt;0000000000000000&gt;] 0x0
  [82039.099150] hardirqs last disabled at (0): [&lt;ffffffffb7884ff2&gt;] copy_process.part.33+0x7f2/0x1f00
  [82039.099545] softirqs last  enabled at (0): [&lt;ffffffffb7884ff2&gt;] copy_process.part.33+0x7f2/0x1f00
  [82039.099925] softirqs last disabled at (0): [&lt;0000000000000000&gt;] 0x0
  [82039.100292] ---[ end trace f2521afa616ddccc ]---
  [82039.100707] WARNING: CPU: 2 PID: 13167 at fs/btrfs/inode.c:9277 btrfs_destroy_inode+0x1ac/0x270 [btrfs]
  (...)
  [82039.103050] CPU: 2 PID: 13167 Comm: umount Tainted: G        W         5.2.0-rc4-btrfs-next-50 #1
  [82039.103428] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
  [82039.104203] RIP: 0010:btrfs_destroy_inode+0x1ac/0x270 [btrfs]
  (...)
  [82039.105461] RSP: 0018:ffffac0b426a7d30 EFLAGS: 00010206
  [82039.105866] RAX: ffff8ddf77691158 RBX: ffff8dde29b34660 RCX: 0000000000000002
  [82039.106270] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8dde29b34660
  [82039.106673] RBP: ffff8ddf5fbec000 R08: 0000000000000000 R09: 0000000000000000
  [82039.107078] R10: ffffac0b426a7c90 R11: ffffffffb9aad768 R12: ffffac0b426a7db0
  [82039.107487] R13: ffff8ddf5fbec0a0 R14: dead000000000100 R15: 0000000000000000
  [82039.107894] FS:  00007f8db96d12c0(0000) GS:ffff8de036b00000(0000) knlGS:0000000000000000
  [82039.108309] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [82039.108723] CR2: 0000000001416108 CR3: 00000002315cc001 CR4: 00000000003606e0
  [82039.109146] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [82039.109567] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [82039.109989] Call Trace:
  [82039.110405]  destroy_inode+0x3b/0x70
  [82039.110830]  btrfs_free_fs_root+0x16/0xa0 [btrfs]
  [82039.111257]  btrfs_free_fs_roots+0xd8/0x160 [btrfs]
  [82039.111675]  ? wait_for_completion+0x65/0x1a0
  [82039.112101]  close_ctree+0x172/0x370 [btrfs]
  [82039.112519]  generic_shutdown_super+0x6c/0x110
  [82039.112988]  kill_anon_super+0xe/0x30
  [82039.113439]  btrfs_kill_super+0x12/0xa0 [btrfs]
  [82039.113861]  deactivate_locked_super+0x3a/0x70
  [82039.114278]  cleanup_mnt+0x3b/0x80
  [82039.114685]  task_work_run+0x93/0xc0
  [82039.115083]  exit_to_usermode_loop+0xfa/0x100
  [82039.115476]  do_syscall_64+0x162/0x1d0
  [82039.115863]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [82039.116254] RIP: 0033:0x7f8db8fbab37
  (...)
  [82039.117463] RSP: 002b:00007ffdce35b468 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
  [82039.117882] RAX: 0000000000000000 RBX: 0000560d20b00060 RCX: 00007f8db8fbab37
  [82039.118330] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000560d20b00240
  [82039.118743] RBP: 0000560d20b00240 R08: 0000560d20b00270 R09: 0000000000000015
  [82039.119159] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f8db94bce64
  [82039.119574] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffdce35b6f0
  [82039.119987] irq event stamp: 0
  [82039.120387] hardirqs last  enabled at (0): [&lt;0000000000000000&gt;] 0x0
  [82039.120787] hardirqs last disabled at (0): [&lt;ffffffffb7884ff2&gt;] copy_process.part.33+0x7f2/0x1f00
  [82039.121182] softirqs last  enabled at (0): [&lt;ffffffffb7884ff2&gt;] copy_process.part.33+0x7f2/0x1f00
  [82039.121563] softirqs last disabled at (0): [&lt;0000000000000000&gt;] 0x0
  [82039.121933] ---[ end trace f2521afa616ddccd ]---
  [82039.122353] WARNING: CPU: 2 PID: 13167 at fs/btrfs/inode.c:9278 btrfs_destroy_inode+0x1bc/0x270 [btrfs]
  (...)
  [82039.124606] CPU: 2 PID: 13167 Comm: umount Tainted: G        W         5.2.0-rc4-btrfs-next-50 #1
  [82039.125008] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
  [82039.125801] RIP: 0010:btrfs_destroy_inode+0x1bc/0x270 [btrfs]
  (...)
  [82039.126998] RSP: 0018:ffffac0b426a7d30 EFLAGS: 00010202
  [82039.127399] RAX: ffff8ddf77691158 RBX: ffff8dde29b34660 RCX: 0000000000000002
  [82039.127803] RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff8dde29b34660
  [82039.128206] RBP: ffff8ddf5fbec000 R08: 0000000000000000 R09: 0000000000000000
  [82039.128611] R10: ffffac0b426a7c90 R11: ffffffffb9aad768 R12: ffffac0b426a7db0
  [82039.129020] R13: ffff8ddf5fbec0a0 R14: dead000000000100 R15: 0000000000000000
  [82039.129428] FS:  00007f8db96d12c0(0000) GS:ffff8de036b00000(0000) knlGS:0000000000000000
  [82039.129846] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [82039.130261] CR2: 0000000001416108 CR3: 00000002315cc001 CR4: 00000000003606e0
  [82039.130684] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [82039.131142] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [82039.131561] Call Trace:
  [82039.131990]  destroy_inode+0x3b/0x70
  [82039.132417]  btrfs_free_fs_root+0x16/0xa0 [btrfs]
  [82039.132844]  btrfs_free_fs_roots+0xd8/0x160 [btrfs]
  [82039.133262]  ? wait_for_completion+0x65/0x1a0
  [82039.133688]  close_ctree+0x172/0x370 [btrfs]
  [82039.134157]  generic_shutdown_super+0x6c/0x110
  [82039.134575]  kill_anon_super+0xe/0x30
  [82039.134997]  btrfs_kill_super+0x12/0xa0 [btrfs]
  [82039.135415]  deactivate_locked_super+0x3a/0x70
  [82039.135832]  cleanup_mnt+0x3b/0x80
  [82039.136239]  task_work_run+0x93/0xc0
  [82039.136637]  exit_to_usermode_loop+0xfa/0x100
  [82039.137029]  do_syscall_64+0x162/0x1d0
  [82039.137418]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [82039.137812] RIP: 0033:0x7f8db8fbab37
  (...)
  [82039.139059] RSP: 002b:00007ffdce35b468 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
  [82039.139475] RAX: 0000000000000000 RBX: 0000560d20b00060 RCX: 00007f8db8fbab37
  [82039.139890] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000560d20b00240
  [82039.140302] RBP: 0000560d20b00240 R08: 0000560d20b00270 R09: 0000000000000015
  [82039.140719] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f8db94bce64
  [82039.141138] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffdce35b6f0
  [82039.141597] irq event stamp: 0
  [82039.142043] hardirqs last  enabled at (0): [&lt;0000000000000000&gt;] 0x0
  [82039.142443] hardirqs last disabled at (0): [&lt;ffffffffb7884ff2&gt;] copy_process.part.33+0x7f2/0x1f00
  [82039.142839] softirqs last  enabled at (0): [&lt;ffffffffb7884ff2&gt;] copy_process.part.33+0x7f2/0x1f00
  [82039.143220] softirqs last disabled at (0): [&lt;0000000000000000&gt;] 0x0
  [82039.143588] ---[ end trace f2521afa616ddcce ]---
  [82039.167472] WARNING: CPU: 3 PID: 13167 at fs/btrfs/extent-tree.c:10120 btrfs_free_block_groups+0x30d/0x460 [btrfs]
  (...)
  [82039.173800] CPU: 3 PID: 13167 Comm: umount Tainted: G        W         5.2.0-rc4-btrfs-next-50 #1
  [82039.174847] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.11.2-0-gf9626ccb91-prebuilt.qemu-project.org 04/01/2014
  [82039.177031] RIP: 0010:btrfs_free_block_groups+0x30d/0x460 [btrfs]
  (...)
  [82039.180397] RSP: 0018:ffffac0b426a7dd8 EFLAGS: 00010206
  [82039.181574] RAX: ffff8de010a1db40 RBX: ffff8de010a1db40 RCX: 0000000000170014
  [82039.182711] RDX: ffff8ddff4380040 RSI: ffff8de010a1da58 RDI: 0000000000000246
  [82039.183817] RBP: ffff8ddf5fbec000 R08: 0000000000000000 R09: 0000000000000000
  [82039.184925] R10: ffff8de036404380 R11: ffffffffb8a5ea00 R12: ffff8de010a1b2b8
  [82039.186090] R13: ffff8de010a1b2b8 R14: 0000000000000000 R15: dead000000000100
  [82039.187208] FS:  00007f8db96d12c0(0000) GS:ffff8de036b80000(0000) knlGS:0000000000000000
  [82039.188345] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [82039.189481] CR2: 00007fb044005170 CR3: 00000002315cc006 CR4: 00000000003606e0
  [82039.190674] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [82039.191829] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [82039.192978] Call Trace:
  [82039.194160]  close_ctree+0x19a/0x370 [btrfs]
  [82039.195315]  generic_shutdown_super+0x6c/0x110
  [82039.196486]  kill_anon_super+0xe/0x30
  [82039.197645]  btrfs_kill_super+0x12/0xa0 [btrfs]
  [82039.198696]  deactivate_locked_super+0x3a/0x70
  [82039.199619]  cleanup_mnt+0x3b/0x80
  [82039.200559]  task_work_run+0x93/0xc0
  [82039.201505]  exit_to_usermode_loop+0xfa/0x100
  [82039.202436]  do_syscall_64+0x162/0x1d0
  [82039.203339]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
  [82039.204091] RIP: 0033:0x7f8db8fbab37
  (...)
  [82039.206360] RSP: 002b:00007ffdce35b468 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
  [82039.207132] RAX: 0000000000000000 RBX: 0000560d20b00060 RCX: 00007f8db8fbab37
  [82039.207906] RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000560d20b00240
  [82039.208621] RBP: 0000560d20b00240 R08: 0000560d20b00270 R09: 0000000000000015
  [82039.209285] R10: 00000000000006b4 R11: 0000000000000246 R12: 00007f8db94bce64
  [82039.209984] R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffdce35b6f0
  [82039.210642] irq event stamp: 0
  [82039.211306] hardirqs last  enabled at (0): [&lt;0000000000000000&gt;] 0x0
  [82039.211971] hardirqs last disabled at (0): [&lt;ffffffffb7884ff2&gt;] copy_process.part.33+0x7f2/0x1f00
  [82039.212643] softirqs last  enabled at (0): [&lt;ffffffffb7884ff2&gt;] copy_process.part.33+0x7f2/0x1f00
  [82039.213304] softirqs last disabled at (0): [&lt;0000000000000000&gt;] 0x0
  [82039.213875] ---[ end trace f2521afa616ddccf ]---

Fix this by releasing the reserved metadata on failure to allocate data
extent(s) for the inode cache.

Fixes: 69fe2d75dd91d0 ("btrfs: make the delalloc block rsv per inode")
Signed-off-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>Btrfs: fix hang when loading existing inode cache off disk</title>
<updated>2019-09-09T12:59:01Z</updated>
<author>
<name>Filipe Manana</name>
<email>fdmanana@suse.com</email>
</author>
<published>2019-07-04T15:24:09Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=7764d56baa844d7f6206394f21a0e8c1f303c476'/>
<id>urn:sha1:7764d56baa844d7f6206394f21a0e8c1f303c476</id>
<content type='text'>
If we are able to load an existing inode cache off disk, we set the state
of the cache to BTRFS_CACHE_FINISHED, but we don't wake up any one waiting
for the cache to be available. This means that anyone waiting for the
cache to be available, waiting on the condition that either its state is
BTRFS_CACHE_FINISHED or its available free space is greather than zero,
can hang forever.

This could be observed running fstests with MOUNT_OPTIONS="-o inode_cache",
in particular test case generic/161 triggered it very frequently for me,
producing a trace like the following:

  [63795.739712] BTRFS info (device sdc): enabling inode map caching
  [63795.739714] BTRFS info (device sdc): disk space caching is enabled
  [63795.739716] BTRFS info (device sdc): has skinny extents
  [64036.653886] INFO: task btrfs-transacti:3917 blocked for more than 120 seconds.
  [64036.654079]       Not tainted 5.2.0-rc4-btrfs-next-50 #1
  [64036.654143] "echo 0 &gt; /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [64036.654232] btrfs-transacti D    0  3917      2 0x80004000
  [64036.654239] Call Trace:
  [64036.654258]  ? __schedule+0x3ae/0x7b0
  [64036.654271]  schedule+0x3a/0xb0
  [64036.654325]  btrfs_commit_transaction+0x978/0xae0 [btrfs]
  [64036.654339]  ? remove_wait_queue+0x60/0x60
  [64036.654395]  transaction_kthread+0x146/0x180 [btrfs]
  [64036.654450]  ? btrfs_cleanup_transaction+0x620/0x620 [btrfs]
  [64036.654456]  kthread+0x103/0x140
  [64036.654464]  ? kthread_create_worker_on_cpu+0x70/0x70
  [64036.654476]  ret_from_fork+0x3a/0x50
  [64036.654504] INFO: task xfs_io:3919 blocked for more than 120 seconds.
  [64036.654568]       Not tainted 5.2.0-rc4-btrfs-next-50 #1
  [64036.654617] "echo 0 &gt; /proc/sys/kernel/hung_task_timeout_secs" disables this message.
  [64036.654685] xfs_io          D    0  3919   3633 0x00000000
  [64036.654691] Call Trace:
  [64036.654703]  ? __schedule+0x3ae/0x7b0
  [64036.654716]  schedule+0x3a/0xb0
  [64036.654756]  btrfs_find_free_ino+0xa9/0x120 [btrfs]
  [64036.654764]  ? remove_wait_queue+0x60/0x60
  [64036.654809]  btrfs_create+0x72/0x1f0 [btrfs]
  [64036.654822]  lookup_open+0x6bc/0x790
  [64036.654849]  path_openat+0x3bc/0xc00
  [64036.654854]  ? __lock_acquire+0x331/0x1cb0
  [64036.654869]  do_filp_open+0x99/0x110
  [64036.654884]  ? __alloc_fd+0xee/0x200
  [64036.654895]  ? do_raw_spin_unlock+0x49/0xc0
  [64036.654909]  ? do_sys_open+0x132/0x220
  [64036.654913]  do_sys_open+0x132/0x220
  [64036.654926]  do_syscall_64+0x60/0x1d0
  [64036.654933]  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fix this by adding a wake_up() call right after setting the cache state to
BTRFS_CACHE_FINISHED, at start_caching(), when we are able to load the
cache from disk.

Fixes: 82d5902d9c681b ("Btrfs: Support reading/writing on disk free ino cache")
Reviewed-by: Nikolay Borisov &lt;nborisov@suse.com&gt;
Signed-off-by: Filipe Manana &lt;fdmanana@suse.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
<entry>
<title>btrfs: migrate the delalloc space stuff to it's own home</title>
<updated>2019-07-04T15:26:17Z</updated>
<author>
<name>Josef Bacik</name>
<email>josef@toxicpanda.com</email>
</author>
<published>2019-06-19T19:12:00Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/wireguard-linux/commit/?id=867363429d706984915cb4b1f299ce05f8413e23'/>
<id>urn:sha1:867363429d706984915cb4b1f299ce05f8413e23</id>
<content type='text'>
We have code for data and metadata reservations for delalloc.  There's
quite a bit of code here, and it's used in a lot of places so I've
separated it out to it's own file.  inode.c and file.c are already
pretty large, and this code is complicated enough to live in its own
space.

Signed-off-by: Josef Bacik &lt;josef@toxicpanda.com&gt;
Signed-off-by: David Sterba &lt;dsterba@suse.com&gt;
</content>
</entry>
</feed>
